Seeing as they design for 50c flow temperature I would think that nothing is too frequent.
My 9kW used to defrost once every 23 minutes at its peak when running at 42c in icing conditions.
It was awful.
Does it matter whether you have the emitters set to radiators vs fan coils Vs underfloor heating?
If emitters were fan coils I’d imagine it would need to use dhw for defrosting
I have emitters set to underfloor to unlock the full range of overshoot and deltaT. I’m currently running an overshoot of 3 and DT of 5. The octopus default is to set emitters to fancoil when using radiators.
Experimenting with setting to fancoil emitters now. It restricts overshoot to 1 degree which is annoying as in the shoulder months a 3 degree overshoot stopped a cycle that often happened about 20mins after starting up (probably due to the heat from the buffer working its way through the system). Tonight should be cold enough for a defrost - we shall see!
I think the overshoot limitation on fan coils was fixed with a software update? There’s another thread around here somewhere… @KnightPhoenix or @matt-drummer might remember
Overshoot was available in fan coils and ufh on my heat pump between 1c and 4c.
It was fixed at 1c on radiators.
I had a firmware update on the heat pump itself in May 2024 and it made the full overshoot adjustment available between 1c and 4c in all three modes.
Daikin had to do this.
I like to run on radiators with a fixed dT of 10c and the lack of full overshoot was an issue.
Running using radiators has always given me the best efficiency with both the 9kW and 8kW.
A lower dT and varying flow rate has never worked the best for me, I like the flow rate at the minimum at all times other than the initial start of a heating cycle. Even that I restrict the flow rate to the minimum possible.
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Did you contact Daikin direct for that firmware update or go via Octopus?
Always through Octopus
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